How to Change a Drive Belt in a Toyota 4-Runner

by Jeffrey Caldwell

The drive belts on a Toyota 4-Runner connect to pulleys on the end of the crankshaft and power various engine accessories, such as the alternator, air conditioning compressor and power steering pump. Over time these drive belts may wear and begin to crack. The belts will also stretch over time and they will need to be tightened. Determining how much the belts have stretched is called measuring for belt deflection. The Toyota 4-Runner has been in production since 1984. Early models utilized a separate drive belt for each pulley, while later models starting in the late 80s to early 90s switched to a serpentine belt system.

Measuring Belt Deflection

Step 1

Place a straight edge or ruler across the two pulleys on the belt you wish to measure.

Step 2

Press your thumb down on the belt half way between the two pulleys.

Step 3

Measure the distance you can press down with your thumb. It should be between 3/8 and 1/2 inch.

If the measurement is greater you must tighten the belt.

Alternator Belt

Step 1

Loosen the alternator belt adjusting bolt on the alternator, using a wrench. Slide the alternator towards the engine.

Step 2

Pull the belt off the pulleys.

Step 3

Slide a new belt over the alternator and crankshaft pulleys.

Step 4

Pull the alternator away from the engine.

Step 5

Tighten the alternator belt adjusting bolt, using a socket.

Step 6

Measure for deflection.

Step 7

Loosen the alternator adjusting bolt and slide the alternator away from the engine, if the deflection measurement is greater that 1/2 inch.

Tighten the alternator adjusting bolt using a socket.

Air Conditioning Compressor Belt

Step 1

Loosen the air conditioning compressor adjusting bolt and slide the compressor toward the engine.

Step 2

Pull the drive belt off the pulleys.

Step 3

Slide the new belt onto the pulleys.

Step 4

Slide the A/C compressor away from the engine and tighten the adjusting bolt.

Step 5

Measure the drive belt for deflection.

Step 6

Loosen the A/C compressor adjusting bolt and slide the alternator away from the engine, if the deflection measurement is greater that 1/2 inch.

Tighten the A/C compressor adjusting bolt.

Power Steering Pump Belt

Step 1

Loosen the power steering pump adjusting bolt and slide the pump towards the engine.

Step 2

Pull the drive belt off the pulleys.

Step 3

Slide the new drive belt over the pulleys.

Step 4

Push the power steering pump away from the engine and tighten the adjusting bolt.

Step 5

Measure for deflection

Step 6

Loosen the power steering adjusting bolt and slide the power steering pump away from the engine, if the deflection measurement is greater that 1/2 inch.

Tighten the adjusting bolt.

Removing a Serpentine Belt

Step 1

Draw a diagram to note the routing of the serpentine belt around the engine accessory pulleys.

Step 2

Locate the tensioner pulley, it will be located between the generator and crankshaft pulleys.

Step 3

Insert a 1/2 inch breaker bar into the tensioner.

Step 4

Move the breaker bar to your left (when facing the front of the engine) to take the tension off the belt.

Pull the belt off the pulleys.

Installing a Serpentine Belt

Step 1

Loosely thread the new belt around the pulleys follow the diagram you drew previously.

Step 2

Move the breaker bar to your left.

Step 3

Slide the new belt over the tensioner pulley.

Release the breaker bar and remove it from the tensioner pulley.

Tip

When replacing the belts it a good idea to inspect the coolant hoses for leaks and excessive wear. Replace as necessary.

Warning

Allow the engine to cool completely before servicing the drive belts. Failure to do so could cause burns.

About the Author

Jeffrey Caldwell has been a freelance writer for over five months and has published over 250 articles on websites like eHow and Trails.com. Caldwell writes articles on a wide range of topics including travel, camping and automotive mechanics. He has a Bachelor of Arts in English from Millersville University.